$OpenBSD: patch-src_Makefile_in,v 1.4 2017/02/06 09:56:49 landry Exp $
--- src/Makefile.in.orig	Sat Dec 24 16:54:05 2016
+++ src/Makefile.in	Tue Jan 24 21:47:47 2017
@@ -455,8 +455,7 @@ lib_LTLIBRARIES = libgeos.la
 # effort to determine this because depending programs should not be
 # using the C++ library.
 libgeos_la_LDFLAGS = \
-    -release @VERSION_MAJOR@.@VERSION_MINOR@.@VERSION_PATCH@ \
-    -no-undefined
+    -no-undefined -lstdc++ -lm
 
 libgeos_la_SOURCES = \
     inlines.cpp
